1. Technical Field
The present invention relates to electrophotographic image forming apparatuses, such as photocopiers, printers, facsimiles, or multifunctional machines having image forming capabilities, which include a lubricant supplying device and process cartridge.
2. Description of the Related Art
For use in image forming apparatuses such as photocopiers and printers, techniques have been known that use lubricant supplying devices for supplying lubricant onto image bearers such as photosensitive drums and intermediate transfer belts.
In an example of such copying machines, non-transferred toner remaining on the photosensitive drum after a transfer process needs to be completely removed by a cleaning blade (cleaning device) making contact with the photosensitive drum. However, when abrasion occurs at the contact portion of the cleaning blade due to friction with the photosensitive drum, the non-transferred toner passes through a gap, due to abrasion, between the cleaning blade and the photosensitive drum, thereby causing a cleaning failure due to the passed-through non-transferred toner or filming (fusion) of the passed-through non-transferred toner onto the photosensitive drum.
For addressing such problems, the lubricant supplying devices apply the lubricant onto the photosensitive drum to reduce a friction coefficient on the photosensitive drum, thereby lessening wear and abrasion of the cleaning blade and the deterioration of the photosensitive drum. As a result, cleaning failure and filming occurring over time can be suppressed.
However, in the conventional lubricant supplying devices, when an end state of a solid lubricant is detected, the lubricant supplying devices are controlled not to perform an operation until replacement maintenance of the solid lubricant is completed. Then, an application of the lubricant onto the photosensitive drum and an image forming operation are interrupted. This interruption causes a big down time for users.
An object of the present invention is to provide an image forming apparatus, which includes a lubricant supplying device and a process cartridge for reducing the down time caused by the replacement maintenance of the solid lubricant even when the end state of the solid lubricant is detected.